U.S. Pat. No. 4,722,752 discloses a method of the kind mentioned in the opening paragraph, in which silicon wafers are immersed for some time for cleaning in a liquid containing hot (90.degree. C.) deionized water. Subsequently, the silicon wafers are lifted from the water slowly (at a speed of about 5 cm/min. This speed is sufficiently low to ensure that the silicon wafers leave the bath in practically dry state. The surface tension then should play a part.
It has been found in practice that in this method of drying contaminations from the liquid can remain on the substrates. It has been found that the known method described a water film having a thickness of a few microns remains on the silicon wafers. This water film then evaporates rapidly, and this may give rise to so-called "drying marks". During drying, the water film can be contracted so that contaminations in the water, which are often of organic or metallic nature, remain in local concentration on the wafers. Such residues can be very disturbing if, for example, the wafers must still be subjected to an etching treatment. They can locally delay the etching treatment or even prevent this treatment. Further, of course dust particles present in the water film also remain on the wafers.